Rotary brush for carpet scrubbing machine



7, 1968 R. M. BARRY ETAL 3,393,422

ROTARY BRUSH FOR CARPET SCRUBBING MACHlNE Filed Jan. 25, 1968 PIES f W;\"J'ORS ROBERT IV. EAR/P7 44/70 .Z KEILIAIG United States Patent3,398,422 ROTARY BRUSH FOR CARPET SCRUBBING MACHINE Robert M. Barry andAnton J. Reiling, St. Paul, Minn., assignors t0 Multi-Clean Products,Inc., St. Paul, Minn., a corporation of Minnesota Filed Jan. 25, 1968,Ser. No. 700,491 3 Claims. (Cl. 180) ABSTRACT OF THE DISCLOSURE A carpetscrubbing brush adapted to be mounted on a scrubbing machine forrotation on a vertical axis and having a horizontally disposed backboardwith downwardly projecting bristles and a plurality of wiper bladesmounted on the underside of the backboard and extending in generallyradial directions through the bristles, the blades being hinged to thebackboard for limited movement about horizontal axes.

Rotary brushes used in rug and carpet scrubbing machines generallyconsist of a horizontally disposed backboard with downwardly projectingbristles with the board adapted to be driven about an upright axis withthe bristles in engagement with the carpet. It is found that if thebrush is also provided with downwardly projecting blades interposedbetween the bristles, such blades will improve the cleaning activity ofthe brush by performing a wiping function on the carpet nap as well asmoving the cleaning solution and lather evenly along the carpet surface.It is also found that the power requirements to drive a brush providedwith such blades, the bristle characteristics being otherwise equal, issome fifteen percent less than in a brush where the blades are not used.

An object of the present invention is to provide a motor driven carpetscrubbing brush with carpet engaging blades interposed between the brushbristles and which are so mounted on the backboard of the brush as tohave a flexing action on the carpet pile portions which the bladesengage.

Another object of the invention is to provide such a brush with bladesmounted to be resiliently supported by the surrounding brush bristlesand to conform to the length thereof as the bristles become shorter byreason of wear or taking a permanent set.

With these objects in view the invention broadly comprises a rotarybrush for use on a carpet scrubbing machine for rotation about anupright axis, the brush having a circular backboard substantiallycovered on its underside with downwardly extending bristles, and aplurality of blades mounted on the underside of the backboard to extendin generally radial directions through the bristles, the blades beingpivoted to the backboard for swinging to a trailing position relative tothe direction of movement of the brush.

The above mentioned and additional objects of the invention will bebrought to light during the course of the following specification,reference being made to the accompanying drawing, in which:

FIG. 1 is a side elevation of the lower portion of a carpet scrubbingmachine with the brush in operative position upon a section ofcarpeting.

FIG. 2 is an inverted plan View of the brush taken on line 2-2 of FIG. 1and looking upwardly. In this view the brush bristles are partiallybroken away to show the wiper blade mountings.

FIG. 3 is an enlarged fragmentary vertical section through the brushshowing the bristles and a blade in sweeping engagement with a sectionof carpet pile.

Referring now more particularly to the drawing refer- 3,398,422 PatentedAug. 27, 1968 See ence numerals will be used to denote like parts orstructural features in the different views. The numeral 10 denotesgenerally the base of a carpet scrubbing machine. Base 10 has a motor 11mounted on a downwardly opening housing or shield 12. The motor 11 is indriving connection with a circular brush mounted within the shield 12and designated generally by the number 14. A handle 15 is connected tothe motor 11 for moving the base over the surface S of a section ofcarpeting.

The brush 14 has a circular backboard or carrying disk 16 substantiallycovered on its underside with downwardly extending bristle tufts 17.Openings 18 are provided in the backboard and at its center the board isprovided with a coupling sleeve 19 for securing the brush 14 to thedrive spindle of the motor 11.

Two sets of wiper blades are provided on the underside of the brush. Theone set of blades denoted at 20 have a length only slightly less thanthe radius of the brush and extend from the center area of the brushtoward the periphery thereof, as seen in FIG. 2. There are four blades20 in the embodiment shown and these are equally spacedcircumferentially on the backboard at ninety degree spacing with theblades slightly offset from the true radius of the backboard. Each bladeis connected to the backboard 16 by means of a hinge 21 allowing theblade to swing rearwardly in a trailing direction relative to thedirection of brush rotation, as seen in FIG. 3.

A second set of wiper blades are denoted by the numeral 22. These areshorter than blades 20 and are disposed intermediate next adjacentblades 20 substantially bisecting the angle therebetween as shown. Theouter ends of blades 22 are approximately the same distance from thecenter of the brush as are the ends of blades 20. Blades 22 are alsoconnected to backboard 16 by hinges here denoted at 23, allowing theblades to swing to a trailing position during brush rotation.

It will be observed that the brush bristles 17 and blades 20 and 22extend substantially the same distance from blackboard 16 so that thefree ends of the bristles and free edges of the blades lie onsubstantially the same plane. Also it will be understood that Weight ofbase 10 rests upon the bristles 17 causing them to deflect slightly.This deflection will be in a trailing direction, as shown in FIG. 3,during rotation of the brush. Blades 20 and 22 are held in extendedpositions by the bristles.

During the cleaning operation the surface S is covered with a liquid orfoam cleaning agent. As the bristles deflect rearwardly as in FIG. 3,the blades will swing rearwardly about the axes of their hingemountings. The blades being resiliently backed by the bristles 17 scrapeover the carpet pile as shown and flip the threads T thereof rearwardlycausing dirt particles resting between the threads to be tossed upwardlyinto the bristle area.

It is accordingly found that the pivotally mounted blades have a moreeffective cleaning action on the carpeting than do fixed blades. Anadded advantage lies in the fact that the blades will automaticallyadjust to the bottom surface plane of the bristles as they wear down.

It is understood that suitable modifications may be made in thestructure as disclosed, provided such modifications come within thespirit and scope of the appended claims. Having now therefore fullyillustrated and described our invention, what we claim to be new anddesire to protect by Letters Patent is:

1. In a floor scrubbing brush adapted for rotation about a vertical axisand having a backboard substantially covered with downwardly extendingbristles, a plurality of blades mounted on the underside of thebackboard in circumferentially spaced positions and extending ingenerally radial directions with respect to said axis, said bladesextending downwardly from the backboard approximately the same distanceas said bristles and being flexibly connected to the backboard, whereinsaid flexible connection-is provided by a-hinge having portionsinterpivoted on a horizontal axis extending longitudinally of the blade.

2. The subject matter of claim 1 wherein the bristles extend along bothsides of the blade in close proximity thereto to resiliently support theblade in extended position. I

3. In a floor scrubbing brush adapted for rotation about a vertical axisand having a backboard substantially covered with downwardlyv extendingbristles, a plurality of blades mounted on the underside of thebackboard in circumferentially spaced positions and extending ingenerally radial directions with respect to said axis, said bladesextending downwardly from the backboardapproximately the same distanceas said bristles and being flexibly connected to the backboard, whereinthere are two sets of said blades with the blades in each set being of adifferent length and being alternately mounted on the backboard but allextending radiallyfromthe center of the brush the same distance, andwith the lower ends of the blades lying on a common plane with the lowerends of the bristles.

I References Cited UNITED STATES PATENTS PETER FEL DMANQPril'n aryExaminer.

